The goal of this proposal is to develop nuclear magnetic resonance (NMR) microscopy and spatially resolved spectroscopy at 360 MHz (8.5 T/8.9cm bore) and 200MHz (4.7T/33cm bore) on single cells, extracted tissues, and small animals with and without tumors and thus assess their feasibility and applicability. The cytoplasmic characteristics and cell dynamics and metabolism of large single cells (more than 100 microns), specifically frogs eggs, will be examined by 1H studies before and after fertilization in vivo. Imaging and spectrosocopic studies conducted on lenses under normal and high glucose media conditions will improve understanding of diabetes and cataractogenesis, since the effects of diabetes on the lens are reflective of its effect on other tissues. Tumors on small animals will be examined by microscopy and localized spectroscopy and the significance of tumor heterogeneity thus addressed. From these studies the morphologic and spectroscopic characteristics of tumors implanted in animals will be obtained and their implications with respect to cancer diagnosis investigated. The resolution limits defined on the 200MHz instrument on rats and rabbits (with and without implanted tumors) will determine the applicability of microscopy to larger systems, specifically humans. The biological systems in these studies are selected because they are well defined, are currently being investigated in this laboratory, and are areas in which application of this technology will have great potential in their understanding and clinical application. The specific objectives of this proposal are (1) to obtain the best possible resolution and define the limits of spatial resolution with NMR microscopy at both fields on different sized biological systems; (2) to perform NMR microscopy on single cells and study cell metabolism, dynamics (division) and compartmentalization; (3) to determine the capability of resolving the structure of cell clusters in intact living tissues (lenses) and small animals (with tumors); (4) to implement 31P and 1H spatially resolved spectroscopy on imaged regions of small animals, lenses and cells (1H only) at both fields and define the resolution limits; and (5) to obtain spatially resolved relaxation times (T1 and T2) and self-diffusion coefficients in selected studies.